Plant growth analysis: allometry, growth and interference in orchardgrass and timothy

A multiple regression procedure was used to evaluate allometric responses to stand age and species population densities in monocultures and mixtures of orchardgrass (Dactylis glomerata L., also known as cocksfoot) and timothy (Phleum pratense L.). In each species the allometry between shoot dry weight and either leaf area or tiller number per plant was studied. Population density treatments affected allometry by changing allometric exponents expressing the ratio of relative growth rates of different plant characteristics. Allometric relationships changed as growth proceeded, and the two species differed in their allometric responses to treatments.